What if COVID-19 comes in waves, as other pandemics have?

The entrance to St. Michael's Hospital on Queen Street is plastered with COVID-19 Assessment Centre signage as a security guard stands out front and a nurse pokes her head out the door to talk to a man asking a question. Kelsey Wilson/Toronto Star

Every indication from past pandemics is that the COVID-19 virus will come in waves, one now, and at least one more in the fall when hospitalizations and deaths rise again.

The dilemma for public health officials is how to persuade the public, once the first wave is over, not to party like there’s no tomorrow, because there will be a tomorrow. And that tomorrow may well be a second, and perhaps more lethal, wave of the virus.

“I’m beginning to think that it’s more and more less likely that we’re going to get back to normal life – which I miss a lot – before at least the summer. And then we need to start preparing ourselves for the potential second wave in the fall,” she said.

David Earn is an applied mathematician with a primary research interest in epidemiology at McMaster University. He co-wrote a study that looked at causes of waves of the 1918 Spanish flu pandemic.

“If a new influenza virus suddenly jumps from aquatic birds or whatever, out of season, then, because everyone is susceptible, it will tend to lead to an epidemic right away rather than waiting for the season where transmission is better,” he said.

With no immunity to the new virus, the population undergoes a lot of infections. And then the onslaught seems to temporarily die off.

The Spanish flu had a summer wave, and fall wave and then a winter wave. It’s estimated it killed 30 to 70 million people. Earn’s study found school openings and closures, outdoor temperatures and behaviour changes contributed to mortality patterns of the Spanish flu. Of these three, the greatest effect was due to behavioural changes, namely social distancing.

Social distancing can be so successful that when summer comes with its warmer temperatures and high humidity – conditions the virus doesn’t like – transmissions might trail off.

“But we would then expect to have another wave in the fall,” Earn said.

“And in order to avoid that we have to continue the social distancing measures.”

It’s not that we can avoid a second wave altogether, he said. “But at least we want to dampen it and keep it as small as possible.”

But how to persuade people to continue to hunker down in their homes when it looks like the virus is in hiatus?

“Can we really just stay inside our homes for a year or two, and not interact much? Well we could presumably not have big sporting events and things like that – people will get frustrated but they’ll cope. But not interacting in smaller groups is going to be very very difficult to sustain,” Earn said.

The lack of information for a plan to deal with waves of viral outbreaks might be a gap in the way the public health community is engaging with the pandemic, according to Valerie Percival, a specialist in public health at Carleton University.

“I think that we need to develop strategies where we identify how do we get people back to work and how to get people out because people can’t live like this. It’s not sustainable in the long term and we can’t print money, we need to get people back to work. So if I were in a position of decision making I would be looking at that problem.”

“Our pandemic muscles atrophied a bit,” said Percival. She thinks trials should be done with essential workers and health-care workers to find out the easiest and quickest way to test. Laid-off employees should be trained to analyze tests and closed-down university and community college labs should be pushed into service. With innovative approaches to intensive testing, it might be possible to get some people back to normal, if they continue to test negative.

Most of all, she thinks people need more reassurance that this disease is manageable, especially if they’re being urged to lie low throughout the summer. As onerous as that kind of social distancing is, she points out the COVID-19 virus is not the pandemic experts always feared would happen.

“The pandemic that we were worried about and still are worried about is the one that replicates the Spanish flu, that hits young people the hardest.”

The Spanish flu wiped out a significant part of a generation of young workers, breadwinners and future community leaders. It largely spared the elderly. But it’s currently people over 80 who are the largest proportion of victims of COVID-19.

“This one will have huge economic consequences but our infrastructure is intact, our workforce is going to be intact,” she said.